MacMuse wrote: 
> from p.154 of the FBII Reference Manual:
> "The volRefNum% parameter changes each time the computer is started. You
> cannot depend on this value to remain consistent, so saving it and
> reusing it at a later date is not possible."

Thanks Roger. I worked many years with FB I, which didn't had that note
in the reference book. I upgraded to FB II only a few weeks ago.
Still, it doesn't explain why SYSTEM(_aplVol) returns a volRefNum% which
is not found by the FN fileExists function.

Best regards,
Michel Verheughe